echo, delay), profesional speaker system, speaker aktif, box speaker, headphone, video tape, stabiliser listrik, stop kontak listrik, sakelar listrik, pengatur arus listrik (regulator listrik), Video compact disc (VCD), tape disk magnet, perangkat lunak komputer, komputer disc, disk dan pita kaset audio dan video, tape recorder, amplifier, speaker, loudspeaker, equalizer, tuner radio, compact disc player, radio, VCD player, DVD player, laser disc player, kabel audio, mikropon, pesawat televisi, kas register, pesawat video, komputer, antenna, antena parabola, booster amplifier, booster antena, ballast, transformator (trafo), audio mixer, profesional power amplifier, sound prosesor ( compressor limiter, active crossover, profesional equalizer